Ubuntu Server locked me out?

[Jason Crain]

Robert Dailey wrote:
> I was using PuTTY to access my Ubuntu Server 8 box remotely, and I 
> accidently pressed CTRL+SHIFT+S. I'm not sure if this is what 
> triggered it, but my PuTTY session immediately ended and I was not 
> able to connect to my linux server anymore. When I try to connect it 
> says connection refused. Did I somehow set Ubuntu to block all 
> connections? I'm not sure what I did...
>
> Just as a side-note, things like my subversion server still work, I'm 
> able to connect to them. However I cannot connect to my SSH server 
> (using Putty). I did a restart of the server (physically) and it still 
> won't let me connect through SSH.

CTRL+S freezes output; CTRL+Q should resume.  These are known as 
XON/XOFF signals.  However, this should not be a permanent condition.  I 
don't know why restarting would not fix it.